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THRESHOLd


    Defines the energy threshold for star density scoring
    Sets thresholds for elastic and inelastic hadron reactions

    See also PART-THR, PHYSICS

     
WHAT(1)
,
WHAT(2)
: not used
WHAT(3)
= threshold kinetic energy for hadron elastic scattering
Default
: same as for particle transport (set by option PART-THR or by default (i.e. the minimum one for which the present physics can work, typically 0.02/0.05 GeV depending on the hadron)
WHAT(4)
= threshold kinetic energy for hadron inelastic reactions
Default
: same as for particle transport, as defined by option PART-THR or by default. The default thresholds are: 0.0 for protons and pions, 0.02 GeV for high energy neutrons, 0.0 for particles which annihilate at rest - but the latter will not undergo any inelastic interaction between the interaction threshold (in the range 0 and 0.050 GeV depending on the hadron), and 0.0 - and between 0 and 0.050 GeV for all other hadrons)
WHAT(5)
: not used
WHAT(6)
= threshold kinetic energy for star scoring
Default
: the same values as set for inelastic reactions (see
WHAT(4)
above)
SDUM
: not used
Default
(option THRESHOLd not given): the threshold for star scoring is set at 20 MeV for protons and neutrons, and at 50 MeV for all other hadrons
Notes:
1) The possibility to change the threshold for elastic scattering or inelastic collisions (
WHAT(3)
and
WHAT(4)
) is not to be used in normal transport problems, but is made available to investigate the relative importance of different processes on the studied problem. 2) For reasons explained in Note 4) to command SCORE, it is recommended to set the threshold for star scoring (WHAT6)) equal to 0.050 GeV overriding the default of 0.020 GeV. A 0.050 GeV cutoff was used in the past to establish so-called omega factors which are still currently used to estimate induced activity (see [Ran70b,Hof75a,Hof75b]). Stars defined in this way do not include those produced by annihilating particles. 3) The threshold for star scoring requested by option THRESHOLd applies ONLY to the output related to options SCORE and USRBIN. The number of stars reported in the summary statistics at the end of the standard output is always based on the actual energy thresholds for nonelastic interactions (except for neutrons for which stars are reported above 20 MeV).
Example 1:
*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...
THRESHOLd 0.0 0.0 2.0 0.0 0.0 0.0
* Switch off elastic scattering of hadrons below 2 GeV
Example 2:
*...+....1....+....2....+....3....+....4....+....5....+....6....+....7....+...
THRESHOLd 0.0 0.0 0.0 0.0 0.0 0.05
* Score stars only above 50 MeV

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